French election

The caricature of Mr Macron, Mr Fillon's main rival, showed the candidate with a hooked nose, wearing a top hat and carrying a red sickle with which he was cutting a cigar.

Mr Macron is not Jewish but the image appeared to take aim at his past in banking. Critics said it was reminiscent of anti-Semitic Nazi propaganda.

Mr Fillon acknowledged the similarity, saying that the cartoon "evoked the images of a dark period of our history and exploited an ideology that I have always fought against".

And he added on Twitter: "Politics is tough but it must remain dignified. I will not tolerate my party using caricatures that use the themes of anti-Semitic propaganda."

Mr Fillon was at one point the favourite to win the presidency but his campaign has been hit by a series of scandals, including an investigation into allegations that he paid his wife €831,400 (£710,000; $900,000) of public funds for work she didn't do.